Metal‐Assisted Synthesis of Diverse Porphyrinoids by Cyclization of an N‐Confused Thia‐Pentapyrrane

Oxidation of thia‐pentapyrrane S‐P4 with terminal β‐linked pyrrole and thiophene units in the presence of various metal ions has been found to afford distinct porphyrinoids. Specifically, N‐confused thiasapphyrin (1), Cu(III) norrole (2), neo‐confused phlorin (3), and p‐benzinorrole (4) were obtained, when S‐P4 was oxidized with p‐chloranil in acetonitrile in the presence of Ni2+, Cu2+, Cd2+, and Co2+, respectively. The structures of 1–4 have been clearly elucidated by NMR spectroscopy, HRMS, and X‐ray crystal diffraction (for 2–4). This work indicates that the oxidative cyclization by linking highly reactive β‐linked pyrrole unit with less reactive thiophene unit assisted by various metal ions shows great potential in the construction of various novel porphyrinoids.